1. Field of the Invention
The invention refers to an electrical connection between contact rails arranged in an axial shaft borehole and the slip ring of an electrical machine including a slip ring bolt, rigidly connected with the contact rail, which is arranged with axial play in a radial shaft borehole and whose radial outer end is connected with the slip ring through an electrical connecting link.
2. Description of the Prior Art
A slip ring supply line includes two copper rails with a semi-circular cross-section which are installed in an axially running shaft borehole. The two supply rails are, on the one hand, connected at their ends with the winding through supply bolts and, on the other hand, with the slip rings through slip ring bolts and contact links. In general, the slip ring bolts and supply bolts are rigidly held in the respective radial shaft boreholes. During operation of the machine, an axial force can be exerted on the shaft so as to bend the same, resulting from different expansions in length of the two supply rails and of the shaft. Bending of the shaft leads then to increased uneven running of the entire turbo-system.
The above given facts have been taken into account in an electrical machine with liquid-cooled rotor according to the U.S. Pat. No. 3,733,502, as the slip ring bolt as well as the supply bolt have been arranged therein in their radial shaft boreholes with axial play. Relative movement is made possible between the supply bolt and the rotor shaft or rotor coil end without causing damage to the parts to be connected with each other, by means of suitably guiding the connecting line between the supply bolt and the rotor coil end. No details can be derived from the above-mentioned U.S. Patent concerning the connection between the slip ring bolt and the slip rings.